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/*
* mx is a small program that prints out the mx records
* for a particular domain
* (c) NLnet Labs, 2005 - 2008
* See the file LICENSE for the license
*/
#include "config.h"
#include <ldns/ldns.h>
static int
usage(FILE *fp, char *prog) {
fprintf(fp, "%s domain\n", prog);
fprintf(fp, " print out the mx for domain\n");
return 0;
}
int
main(int argc, char *argv[])
{
ldns_resolver *res;
ldns_rdf *domain;
ldns_pkt *p;
ldns_rr_list *mx;
ldns_status s;
p = NULL;
mx = NULL;
domain = NULL;
res = NULL;
if (argc != 2) {
usage(stdout, argv[0]);
exit(EXIT_FAILURE);
} else {
/* create a rdf from the command line arg */
domain = ldns_dname_new_frm_str(argv[1]);
if (!domain) {
usage(stdout, argv[0]);
exit(EXIT_FAILURE);
}
if (! ldns_dname_str_absolute(argv[1]) &&
ldns_dname_absolute(domain)) {
/* ldns_dname_new_frm_str makes absolute dnames always!
* So deabsolutify domain.
* TODO: Create ldns_dname_new_frm_str_relative? Yuck!
*/
ldns_rdf_set_size(domain, ldns_rdf_size(domain) - 1);
}
}
/* create a new resolver from /etc/resolv.conf */
s = ldns_resolver_new_frm_file(&res, NULL);
if (s != LDNS_STATUS_OK) {
exit(EXIT_FAILURE);
}
/* use the resolver to send a query for the mx
* records of the domain given on the command line
*/
p = ldns_resolver_search(res,
domain,
LDNS_RR_TYPE_MX,
LDNS_RR_CLASS_IN,
LDNS_RD);
ldns_rdf_deep_free(domain);
if (!p) {
exit(EXIT_FAILURE);
} else {
/* retrieve the MX records from the answer section of that
* packet
*/
mx = ldns_pkt_rr_list_by_type(p,
LDNS_RR_TYPE_MX,
LDNS_SECTION_ANSWER);
if (!mx) {
fprintf(stderr,
" *** invalid answer name %s after MX query for %s\n",
argv[1], argv[1]);
ldns_pkt_free(p);
ldns_resolver_deep_free(res);
exit(EXIT_FAILURE);
} else {
ldns_rr_list_sort(mx);
ldns_rr_list_print(stdout, mx);
ldns_rr_list_deep_free(mx);
}
}
ldns_pkt_free(p);
ldns_resolver_deep_free(res);
return 0;
}
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